http://www.microsoft.com/Education/CaseStudies.mspx
This website gives great example of how schools have used case studies to improve their students academically. On this page there are links to the case studies down by different school around the country, you can also go to their search data base and search for other case studies whether academic or not. However, most of these case studies only deal with the technology in the schools, it would be nice to see some of them deal with classroom techniques. Finally their are also links to lesson plans for teachers and students use.

http://goliath.ecnext.com/coms2/gi_0199-1258602/Designing-multimedia-case-studies-for.html
This web site is actually an article that talks about how to design a multimedia case study for future mathematics teachers. It also gives an example of how to do it. I this site would be much better if there were link to other example of case studies done it mathematics.

http://ublib.buffalo.edu/libraries/projects/cases/case.html
This web site is the national website for case studies in teaching science. The web site provides many links, for example summer workshops, UB case study collection, case study teacher, journals, other case websites, and related websites. This is the better one of the three that I have found information on.